On six occasions, a president took the oath of office one or (in Tyler's case) two days after the beginning of his term of office, either because the demise of the presidency was due to the death of the incumbent or because of religious scruples about swearing an oath on Sunday. These occasions are: Monroe1821 (upon reelection), Tyler1841, Taylor1849, Fillmore1850, Arthur1881, Coolidge1923. Although the oath is necessary for a president to "enter on the execution of the office," the presidential term itself begins on time. On two occasions the new president took the oath of office in public the day after the beginning of the term but, in view of the concerns voiced about earlier Sunday deferrals, had taken the oath in private (Hayes1877 actually one day early). The beginnings of the terms are listed here, not the oath-taking dates. It may be noted in this context that there is no substance to the legend that David Rice Atchison was president 4-5 Mar 1849. (If not being sworn in as president is held against Zachary Taylor's being president already from noon on 4 Mar 1849, it cannot be argued that another person, however qualified otherwise, could have been acting president without being sworn in in that capacity.)